Meteorites – Nature’s gifts from the sky

We were up very early last week hoping to see the Leonid meteorite shower, but unfortunately we have a huge hill behind our property that obscured our view.  The Leonid shower occurs every year in November, but this year it was more visible than usual due to the phase of the moon being new,  making the night sky much darker than in previous years.

I have mentioned in earlier blogs that the Namibian sky is spectacular for astronomy – one can almost always be guaranteed a cloud-free view of the milky way, millions upon millions of beautiful stars, meteorites and occasional comets.

On the subject of meteorites, though, did you know that the largest meteorite in the world is found in Namibia?  I’m referring to the Hoba meteorite near Grootfontein.  This magnificent object landed some 80 000 years ago – hopefully there were no humans or animals directly in its path!

The Hoba meteorite found on the farm 'Hoba West'

The Hoba meteorite found on the farm 'Hoba West'

It didn’t break up on its journey to the earth, however, and to quote Wikipedia “it is inferred that the earth’s atmosphere slowed the object down to the point that it fell to the surface at terminal velocity, thereby remaining intact and causing little excavation.  The meteorite is unusual in that it is flat on both the major surfaces, possibly causing it to have skipped across the top of the atmosphere in the way a flat stone skips on water.”

Weighing in at over 50 tons - this is one big meteorite

Weighing in at over 50 tons - this is one big meteorite

The meteorite has been declared a National Monument and a tourist centre has been opened at the site.   Every year thousands of visitors come to Namibia to see it or include it in their travels.  This board gives a little bit more information about its composition.

Information board at the Visitors Centre

Information board at the Visitors Centre

In Windhoek’s Post Office Mall one can see fragments of the Gibeon meteorite shower, which was one of the most extensive showers ever experienced on earth.  They have been beautifully mounted and tagged so that visitors can read all about how they fell and what they are composed of.   Other fragments can be seen at the museum of the Geological Survey of Namibia and in museums around the world.

Far more visible than being in a museum

Far more visible than being in a museum

They were discovered in 1838 by James Alexander and get their name from the area around Gibeon where they were found.  Long before their discovery the native folks of the Gibeon area had been using the meteorite pieces to make spear points and other implements.

A look inside a meteorite

A look inside a meteorite

The Gibeon meteorites are classified as octahedrites and consist of taenite and kamacite – crystalline varieties of an iron-nickel alloy.  As can be seen from the scratches on the metal above, vandalism is always a problem – or is it just curiosity?

2 thoughts on “Meteorites – Nature’s gifts from the sky

  1. Pete Bowen

    Hi there

    Read your article a couple of days ago and then I was browsing through the News and saw that a new meteor has been spotted flying at a rate of knots over Gauteng. The science guys are not too sure where it landed but it was sighted over Gauteng, Mpumalanga, Limpopo and Botswana.

    Check out the link for the video:

    Cheers

    Pete

    Reply

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